Datasheet

Modifications

1-4

1.3 Modifications

The TPS54372EVM-215 is designed to demonstrate the small size that can

be attained when designing with the TPS54372. Many

of the features that

allow for extensive modifications have been omitted from this EVM. The output

voltage V

(TTQ)

can be set in the range of 6% of V

to 1.75 V by changing the

(DDQ)

voltage input at J3. The output V

(TTQ)

will track at one half the V

(DDQ)

voltage. The lower voltage limit is set by the minimum on time of the

TPS54372. The upper voltage limit is set by the internal voltage reference.

Larger output voltages up to 90% of V

are possible in designs using the

TPS54372, but are not supported on this evaluation module.

The switching frequency may be trimmed to any value between 280 kHz and

700 kHz by changing the value of R5. Decreasing the switching frequency

results in increased output ripple unless the value of L1 is increased. A plot of

the value of RT versus the switching frequency is given in Figure 1–1.

Figure 1–1. Frequency Trimming Resistor Selection Graph

250

300

350

400

450

500

550

600

650

700

750

60 70 80 90 100 110 120 130 140 150 160 170 180

Switching Frequency – kHz

R – Resistance – kΩ